Zoology and wildlife conservation

An unusual feature revealed by the crystal structure at 2.2A resolution of human transforming growth factor-beta-2

Article Abstract:

The human transforming growth factor type beta-2 (TGF-beta-2) has an unusual crystal structure marked by a monomer fold and dimer association. TGF-beta-2 is important because of its role in many aspects of cell proliferation and development including wound healing, bone growth and immunological modulations. Examination of TGF-beta-2 at 2.2 angstrom resolution found that the monomer was made up of two antiparallel sets of beta-strands forming a flat curved surface and a separate, long alpha-helix. This model should lead to an understanding of TGF-beta-2's effects on receptors.

Long-term proliferation of mouse primordial germ cells in culture

Article Abstract:

The long-term in vitro survival and growth of primordial germ cells (PGCs) has been achieved for the first time by using basic fibroblast growth factor as well as steel factor and leukemia inhibitory factor to stimulate proliferation. Enhancement of PGC proliferation by these three factors produces large colonies of embryonic germ cells that are necessary for further embryonic development. These embryonic germ cells are similar to embryonic stem cells and to feeder-dependent embryonal carcinoma cells.

Cell transformation and activation of pp60c-src by overexpression of a protein tyrosine phosphatase

Article Abstract:

Genetic overexpression of the receptor-like protein tyrosine phosphatase PTP-alpha stimulates cell transformation and tumorigenesis by activating the pp60c-spc kinase. Moreover, dephosphorylation at Tyr 527 occurs along with pp60c-spc activation in PTP-alpha-overexpressed cells. These findings indicate that PTP-alpha helps to control cell proliferation but can trigger the growth of tumors when overexpressed.